Adobe Digital Edition not working with kobo Forma

[coccinella63]

I got a book from my university library, but can't read in Kobo Forma.

The message is (translated from italian): "your ereader is not authorized by Adobe Digital Editions (DRM). Because you previously erased authorization of your ereader you must re-import your book..."

I deleted authorization and reenabled it a lot of times even from ADE and Kobo, connected it and disconnected and so on, as from documentation paper, but with no results.

I can download the book, I can read it in ADE, I can move it in the ereader, but when I open the ereader I see the cover of the book black, and when I try to open it I get the message again.

Thanks so much for help.

[Asamlie2010]

I'm having the identical problem. While I've had this problem intermittently over the last several years, this time it finally will not be fixed by following various fixes that have worked for others, including the following in multiple combinations:

- Deleting and reinstalling ADE

- Reverting to ADE 3.0 (no longer an option in Mac OS Catalina)

- Deauthorizing and reauthorizing both ADE and my eReader (Kobo Aura)

- Deleting the authorization file (.dat) in Library > Application Support > Adobe > Digital Editions

- Deleting old .acsm files I'd borrowed from my library (Documents > Digital Editions)

- Resetting my eReader to factory settings

- Rebooting my computer multiple times at various stages of the above actions

- Doing all of the above, borrowing a completely new book from the library into ADE

As of 2 days ago, I have been trying to download 4 books from the library. One of them originally worked but no longer does. When I download and open in ADE, multiple versions of that file - and the other 3 that I have fully deleted from my computer and not yet re-downloaded from the library - show up in ADE. Every. Single. Time. These files show up as Cloud Sync files in Documents > Digital Editions, even though I do not have the sync option activated in ADE. One of the books is one I have read previously (aka I can guarantee it has worked on my eReader before). I've tried manually deleting all Cloud Sync files both before and after transferring a book in ADE to my eReader.

Every book I download opens fine in ADE (despite the multiple copies that show up in ADE), but once transferred to my eReader, they show a full black cover and tell me "Your eReader is not authorized to open this book. This book is protected by Adobe Digital Rights Management (DRM). Because you previously deauthorized your eReader, you need to re-import the book using Adobe Digital Editions (ADE). Please visit help.kobo.com for more information."

I do not live on a continent where I can get physical library books, my wifi is not unlimited and therefore it's costly to keep deleting, reinstalling, resetting, etc.

Running this on Mac OS 10.15.5 (Catalina), ADE 4.5.11.187245, Kobo Aura eReader 4.22.15190.